The recovery of the ecological-materialist foundations of Karl Marx's thought, as embodied in his theory of metabolic rift, is redefining both Marxism and ecology in our time, reintegrating the critique of capital with critical natural science. This may seem astonishing to those who were reared on the view that Marx's ideas were simply a synthesis of German idealism, French utopian socialism, and British political economy.… The rediscovery of Marx's metabolism and ecological value-form theories, and of their role in the analysis of ecological crises, has generated sharply discordant trends. Despite their importance in the development of both Marxism and ecology, neither idea is without its critics. One manifestation of the divergence on the left in this respect has been an attempt to appropriate aspects of Marx's social-metabolism analysis in order to promote a crude social "monist" view based on such notions as the social "production of nature" and capitalism's "singular metabolism." Such perspectives, though influenced by Marxism, rely on idealist, postmodernist, and hyper-social-constructivist conceptions, which go against any meaningful historical-materialist ecology and tend to downplay (or to dismiss as apocalyptic or catastrophist) all ecological crises—insofar as they are not reducible to the narrow law of value of the system.